<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>jQuery 文档操作</title>
    <script type="text/javascript"src="../js/jquery-3.3.1.js"></script>
    <script type="text/javascript">//对html代码的操作
        $(document).ready(function () {
            //给div附上内容
            $("div").html("<h1 style='background: cyan'>HLOmaster</h1>")
            //获取div 内容
            var $html=$("div").html();
            alert($html);
        })
    </script>

</head>
<body>
      <div></div>
</body>
</html>